4/15/2008 @ 4:00PM

How To Calculate Your Carbon Footprint

Whether by lowering your thermostat or unplugging seldom-used appliances, chances are you’ve recently attempted to scale back on energy use.

In fact, you may be one of the consumers who have bought more than 1.5 billion Energy Star-qualifying products since the label was introducedin1992. Last year, one in three people reported using the label as part of a purchase decision, according to the Environmental Protection Agency. If they’d bought an Energy Star-qualified commercial dishwasher, they might be saving an estimated $200 per year, according to the Department of Energy. Those that took home an Energy Star refrigerator can look forward to a 15% less expensive monthly electricity bill.

Other ways of saving energy include fixing a leaky faucet and checking your insulation levels. But the most comprehensive way might be to figure out exactly how much damage you’re inflicting so you’ll know how much to cut back.

Author Alexandra Shimo-Barry knows how. In her new book, The Environment Equation, Shimo-Barry, a national reporter for Maclean’s in Canada, teaches readers how to quickly calculate their carbon footprints, or the amount of greenhouse gases in units of carbon dioxide, they’re producing by using the following formula:

A.) Multiply your monthly electricity bill by 105

B.) Multiply your monthly gas bill by 105

C.) Multiply your monthly oil bill by 113

(if you don’t use either B or C, enter 0.)

D.) Multiply total yearly mileage by .79

E.) Multiply the number of flights–4 hours or less–by 1,100

F.) Multiply the number of flights–4 hours or more–by 4,400

G.) Do you recycle newspaper? If no, add 184. If yes, add 0.

H.) Do you recycle aluminum and tin? If no, add 166. If yes, add 0.

A+B+C+D+E+F+G+H = your carbon footprint. A number below 6,000 (reflected in pounds per year) is excellent. Over 22,000? Not so great. Good is anywhere from 6,000 to 15,999, while 16,000 to 22,000 is average.

If your number is higher than you would like, there’s good news–there are hundreds of ways you can shrink your carbon footprint, and many of them aren’t as sacrificial as you might expect.

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That’s because Shimo-Barry says that lack of will, not austere alternatives, is the No. 1 barrier blocking would-be waste-reducers.

“There’s still inertia when it comes to making small changes,” she says. “But Americans emit 20 tons of carbon dioxide per year. Even if we cut that by a ton–which isn’t difficult–it would make a huge difference.”

Simple Steps

Eating locally grown food is one of the easiest ways to reduce your footprint. Whether you begin visiting the farmer’s market every Saturday to pick up local fruits and vegetables or, if you are able, dining at restaurants serving regional fare, eating locally allows you to eat well without funding the emissions used to import food from other countries and regions.

Jason Karas, founder of Cambridge, Mass.-based Carbonrally.com–a gaming Web site that challenges users to reduce personal emissions through online competitions–says that drinking locally microbrewed beer is another way to shrink your footprint, for much the same reasons as eating regional food.

“It’s also a great way to support local entrepreneurs,” says Karas.

Buying second-hand is another luxurious choice. For many, vintage shopping has become as chic as getting on the list for the newest pair of Christian Louboutins. Buying vintage clothing and accessories is more than looking sharp: These practices will reduce your carbon footprint by eliminating the energy it takes to produce something new. What’s more, you might get that Hermes Birkin for $2,000 instead of $8,000. Those not so used to buying second-hand should read “Shopping Tips for Vintage Clothing Collectors.”

How are you cutting back on energy use? Weigh in. Add your thoughts in the Reader Comments section below.

Sustainable wood furnishings are another smart lifestyle alternative. Before you redecorate your home by raiding the Conran Shop, consider buying pieces from eco-friendly shops like Vivavi and Environment Furniture. Both offer stylish, modern goods–like a mid-century-styled credenza or a curvy bamboo rocking chair–that are Forest Stewardship Council-certified, which means they’ve met 57 earth-friendly criteria established by the organization. These include minimal pesticide use, protection of local wildlife and unionization for loggers.

In the market for a second home? A penthouse on Central Park South might not sound like the most efficient way to cut carbon, but city living is often friendlier to the environment. That’s because many urbanites rely on public transportation. And even a two-floor penthouse in the Trump Tower uses far less energy than a sprawling seven-bedroom mansion. What’s more, when water, sewage and electricity are shared, less copper–which is found in plumbing and electrical systems and is one of the largest contributors to landfills–is needed.

All evidence that living grandly can do the earth well, as long as you know where to cut back.